The Naked Scientists

The Naked Scientists Forum

Author Topic: "Another Hockey Stick Illusion"?  (Read 47925 times)

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #25 on: 17/04/2011 11:36:14 »
Hi rosy, thanks for applying your mathematical and “Google” talents to the question of how much air there might be in an iceberg, although you stopped before you arrived at an answer. How about developing your analysis a little further by taking into consideration the difference between the “ .. average density of seawater at the ocean surface  .. ” offered by Wikipedia (http://en.wikipedia.org/wiki/Seawater) and the actual density of seawater surrounding an iceberg. That will be much more useful in aiding our understanding of how “solid” the ice in an iceberg really is.

Your
Quote
Do you think a lump of ice composed of 10 % air bubbles by volume would be strong enough to withstand being pulled out of the ground with an ice-core drill? Seems rather unlikely to me. Ice is brittle stuff
suggests that you haven’t spent much time researching ice cores or much time trying to understand my question about “Another Hockey Stick Illusion?”. As you may not have realised, my question here relates mainly to the process of size-dependent fractionation occurring in the firn, not in the “solid” ice (although there is further fractionation there too). According to your speculative comment it should not be possible to remove ice cores from firn but I am not aware that there is a problem there. Maybe you can provide a link to evidence supporting your opinion on this.

A Google search will take you to some interesting papers, including pictures, which should clarify this for you. Yes, those cores a brittle and need very careful handling, but those ice core experts are able to extract long cores even from the much less dense firn above that solid ice. They are so clever at it
Quote
.. Using the PICO (Polar Ice Coring Office) lightweight auger, a 31 m long firn core was drilled adjacent to the cane farm at GD03. The GD03 core represents 55 years of annual snow-accumulation increments which were interpreted from the combined stratigraphic analyses of density, oxygen-isotope and visible layering. A vertical profile of density .. shown in Figure 2 ..
, (http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/henry.html Page 385 of the source document). Perhaps you should have a good look at the density graph in Fig. 2 before responding.

Hi Wiybit, I was disappointed that none of this “ .. media-savvy group of physicians and researchers from Cambridge University .. ” have tried to help you out on your
Quote
.. fickian law  .. looks to relate more to solids then gases ..
. I’d love some help on the relevant laws of diffusion too and since none of The Naked Scientists seems to be able to help I took the opportunity of chatting about that (and my question about “Another Hockey Stick Illusion?”) with Professor Andrew White who was visiting us this weekend.

Dr. White is Professor and Director, Center for High Energy Physics Research and Technology, Department of Physics, The University of Texas at Arlington and has been a Professor of Physics there for 20 years (http://www.uta.edu/physics/main/faculty/). During that time he has been involved in research at CERN so I thought that he could perhaps save me some time digging up an answer for you. As Bored chemist might say “Nope”. His response was “I’m not up on diffusion” so I had to try elsewhere. Does this help
Quote
Fick's Law: The net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane and inversely proportional to the thickness of the membrane. Combined with the diffusion rate determined from Graham's law, this law provides the means for calculating exchange rates of gases across membranes
(http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/henry.html)?

Geezer, I hope that you were able to spot the point I was making about Dr. White's response to my question. I’ll also mention that I discussed your
Quote
.. I find it interesting that anyone who is unaware of why ice cubes float in water might think they are qualified to call into question the scientific credentials of anyone else ..
and you’ll also find it interesting that he does not share you implied opinion. His appears to be completely opposite to yours. Why not drop him an E-mail (awhite@uta.edu) and ask him. After all unlike either of us (and many of those who support the CACC doctrine), he is a highly respected scientist.

Best regards, Pete Ridley
« Last Edit: 17/04/2011 19:38:25 by Pete Ridley »
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #26 on: 17/04/2011 13:40:20 »
Hi Wiybit, I was disappointed that none of this “ .. media-savvy group of physicians and researchers from Cambridge University .. ” have tried to help you out on your
Quote
.. fickian law  .. looks to relate more to solids then gases ..
.

Seriuosly you shouldn't encourage them(if you get me). :)



I’d love some help on the relevant laws of diffusion too and since none of The Naked Scientists seems to be able to help I took the opportunity of chatting about that (and my question about “Another Hockey Stick Illusion?”) with Professor Andrew White who was visiting us this weekend.

Andrew is Professor and Director, Center for High Energy Physics Research and Technology, Department of Physics, The University of Texas at Arlington and has been a Professor of Physics there for 20 years (http://www.uta.edu/physics/main/faculty/). During that time he has been involved in research at CERN so I thought that he could perhaps save me some time digging up an answer for you. As Bored chemist might say “Nope”.

Yeah BC can be slightly funny at times, but generally he's ok, when not going on about dance routines and stuff, and trying to catch you out(so he can laugh at you)  :) Completly said it light hearted jest BC so don't start.


 His response was “I’m not up on diffusion” so I had to try elsewhere. Does this help
Quote
Fick's Law: The net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane and inversely proportional to the thickness of the membrane. Combined with the diffusion rate determined from Graham's law, this law provides the means for calculating exchange rates of gases across membranes
(http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/henry.html)?

Thanks, I'll check it out. Yet you still haven't said what it is about Co2 that causes it to act so differently to the other elements, surely HE should move more, in ice if it's smaller and lighter?
« Last Edit: 17/04/2011 13:55:49 by Wiybit »
 

Offline rosy

  • Neilep Level Member
  • ******
  • Posts: 1018
  • Chemistry
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #27 on: 17/04/2011 14:00:49 »
Quote
suggests that you haven't spent much time researching ice cores or much time trying to understand my question about “Another Hockey Stick Illusion?”.
Wrong, I've spent no time at all researching ice cores or trying to understand your question. I'm not an expert, and I certainly don't have sufficient free time to do the necessary research, so I leave it to other people.

I'm going to be rude, now. I usually try not to be too rude online, but on this occasion I am completely out of patience, both with your approach to science and with your personal demeanour.

Moreover, I certainly would not trouble to put in all that legwork to answer a question from you, Pete, because although your initial ignorance of what causes ice to float is (just about) understandable, although surprising in someone who claims to have been taking an interest in climate change issues for some time, your apparent failure to make even a token effort to understand what's actually going on by making a few back-of-the-envelope calculations of your own leads me to believe that even if I understood, and explained, it wouldn't improve your understanding because you are more interested in a quasi-religious fight against "the climate change establishment" than in obtaining any level of personal understanding of the field in order to be able to make an intelligent contribution. This is for exactly the same reason I don't bother to argue with creationists about evolution.

Now, if anyone is actually interested (and I acknowledge this isn't rocket science...), the densities of water at different temperatures are given here:
http://www.sfu.ca/physics/ugrad/courses/teaching_resources/demoindex/fluids/fl2b/density.html
The density of pure water is, at least, 0.998 (density at 0 oC, density at 4 oC is a little higher. If the ice (at 0.92) were floating entirely on its own (pure) melt-water, it would float with 8.5 % of its volume above the water. But the water is not pure, it is mixing all the time with salt sea-water, so it might be fractionally less dense than the average surface water density (1.02-1.03), but the absolute lower limit is that 8.5 % will float above the surface, in reality it will be more, and that's entirely without considering the effects of air bubbles.
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #28 on: 17/04/2011 17:15:39 »
Now, if anyone is actually interested (and I acknowledge this isn't rocket science...), the densities of water at different temperatures are given here:
http://www.sfu.ca/physics/ugrad/courses/teaching_resources/demoindex/fluids/fl2b/density.html
The density of pure water is, at least, 0.998 (density at 0 oC, density at 4 oC is a little higher. If the ice (at 0.92) were floating entirely on its own (pure) melt-water, it would float with 8.5 % of its volume above the water. But the water is not pure, it is mixing all the time with salt sea-water, so it might be fractionally less dense than the average surface water density (1.02-1.03), but the absolute lower limit is that 8.5 % will float above the surface, in reality it will be more, and that's entirely without considering the effects of air bubbles.

Rosy, doesn't water compact as it frezzes? shouldn't the density be highier at 0, as the atoms are more compacted, than at 4 oC?

If it is a little higher density at 4 oC than at 0oC that suggests the water compacts as it warms. Doesnt it? Or is it that as the ice melts or starts to, air is realesed and the water comes closer together? That would work from Ice to water but not the other way round.
« Last Edit: 17/04/2011 17:21:41 by Wiybit »
 

Offline rosy

  • Neilep Level Member
  • ******
  • Posts: 1018
  • Chemistry
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #29 on: 17/04/2011 17:30:41 »
Quote
Rosy, doesn't water compact as it frezzes? shouldn't the density be highier at 0, as the atoms are more compacted than at density at 4 oC?
No. Water doesn't compact as it freezes, and the maximum density of water occurs at 4 oC. Water's funny stuff. I'm not going to try to explain in any detail here, because it needs diagrams, but there's lots of information on the internet about this. For example this page: http://kentsimmons.uwinnipeg.ca/cm1504/water.htm

On a more hands-on level, consider an ice cube made in your freezer to cool a drink. Not being made from snow, it doesn't contain (a significant number of) bubbles, and yet it floats. If you think about it, I'm pretty sure this is something you know and understand! The density of ice is, inherently, less than that of water at the same temperature. Equally, if you close up a bottle full to the top with water at room temperature (using a plastic bottle is important for safetly..), and freezing the water, the bottle will split as the water expands on forming ice... which shows you that the same mass of water takes up more space (is less dense) when frozen than as a liquid.

Incidentally, if ice didn't float, and if the coldest water didn't float on top of water at 4 oC, then the coldest water would sink to the bottom of lakes and rivers, and they'd freeze from the bottom up. That would mean that instead of a layer of ice over liquid water the whole of the lake would freeze, which would kill the fish and other animals living in the water whereas in reality they can hide in the relatively warm water at the bottom until spring.
 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #30 on: 17/04/2011 17:49:08 »
Hi Wiybit, sorry that I didn’t have time to respond straight away to the points you raised on 16/04/2011 @ 20:48:50 and today @ 13:40:20. I don’t want to get distracted from the focus of my question about “Another Hockey Stick Illusion?”, i.e. why the “experts” ignore kinetic in favour of collision diameter. If it’s OK with you I’ll leave it to the Naked Scientists to respond to any that I see as a side-issue. You may have to raise such questions separately in order to attract their attention.

Quote
.. Seriuosly you shouldn't encourage them(if you get me) ..
is not the reason that I joined this blog. I will do my utmost to encourage The Naked Scientists to offer their expertise where it relates to my question. I’m very disappointed that I’ve had nothing from them yet and the appropriate laws of molecular dynamics covering the movement of atmospheric gases in firn are certainly relevant.

Quote
.. BC can be slightly funny at times, but generally he's ok, when not .. trying to catch you out(so he can laugh at you) ..
is fine for anyone who has come here to be amused but I’m not in that category. I’m here to learn as much as I can about the science relevant to my question. So far the only person on this blog to help improve my understanding is you through your questions.

Regarding
Quote
.. you still haven't said what it is about Co2 that causes it to act so differently to the other elements, surely HE should move more, in ice if it's smaller and lighter? ..
one day I may be able to fully answer the first part with confidence. All that I can say for the moment is that it is something to do with the bonding between the one C and two O atoms that make up a molecule and the interaction of each molecule with other molecules (N2, O2, Ar, CH4, H2O, etc. Why not put that question to The Naked Scientists.

As for the second part, He, being smaller even than CO2, does experience size-dependent fractionation, as described in the paper “Evidence for molecular size dependent gas fractionation in firn air derived from noble gases, oxygen, and nitrogen measurements” by Huber et al (http://icebubbles.ucsd.edu/Publications/Huber_closeoff_EPSL2006.pdf).

It is worthwhile looking more closely at that paper, because as well as answering your question about He directly, it expands on my earlier comment (on 14/04/2011 21:38:13) about Huber, Severinghaus (one of the co-arthors) and that magic 0.36nm molecule diameter
Quote
Abstract .. For smaller gas species (mainly He and Ne) the fractionation factors are linearly correlated to the molecule size, whereas for diameters greater than about 3.6 Å the fractionation seems to be significantly smaller or even negligible ..

Note that Table 2 presents the molecular diameters used in their model and the close-off fractionation factor it produced for 8 of the atmospheric gases, including CO2 and He, but also note that those diameters are collision, not kinetic. Fig. 8 presents a useful graph of 7 of those computer-modelled close-off fractionation factors, with He down at the bottom of the curve, but note which one is missing, dear old CO2. I mentioned in that earlier comment that I had asked Severinghaus why he used collision rather than kinetic diameter and if he had tried his model using CO2’s 0.33nm kinetic diameter instead of its 0.39nm collision diameter. As I said, he chose not to respond directly to those questions. Have a guess where CO2 would have been if he had used kinetic diameter, which I hypothesise is the appropriate measure.

That is why I challenge the conclusion that
Quote
.. Close-off fractionation factors for different gases depend strongly on the diameter. The mass of the molecule is less important, since the effect on isotope ratios is very low. The critical size of about 3.6 Å seems to be an upper limit up to which molecules fractionate during the close-off process in the firn. A possible explanation for this could be the diffusion of molecules through channels in the ice lattice. From our findings we believe that the effect of close-off fractionation is nonexistent or at least very small for isotope ratios and for large molecules, like Xe, Kr, N2, CO2, CH4, and N2O. This is an important confirmation for the integrity of polar ice cores as a climate archive of the ancient atmospheric composition of these gases ..

But I’m only a retired Chartered Electrical Engineer and Geezer reasonably says
Quote
.. I find it interesting that anyone who is unaware of why ice cubes float in water might think they are qualified to call into question the scientific credentials of anyone else ..
That is why during the past year I have requested help from “experts” like Severinghaus, Alley, Bender, etc. etc. etc. and now from this “ .. media-savvy group of physicians and researchers from Cambridge University .. ”, but I’m still not getting an answer.

BTW, that paper also gives figures for
Quote
.. Firn density at surface [g/cm3] 0.40 0.32 .. Firn density at close off [g/cm3] 0.838 0.811 ..
which you (and others here) should find helpful.

Best regards, Pete Ridley.
« Last Edit: 17/04/2011 18:07:23 by Pete Ridley »
 

Offline Geezer

  • Neilep Level Member
  • ******
  • Posts: 8328
  • "Vive la résistance!"
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #31 on: 17/04/2011 19:03:07 »

On a more hands-on level, consider an ice cube made in your freezer to cool a drink. Not being made from snow, it doesn't contain (a significant number of) bubbles, and yet it floats. If you think about it, I'm pretty sure this is something you know and understand! The density of ice is, inherently, less than that of water at the same temperature. Equally, if you close up a bottle full to the top with water at room temperature (using a plastic bottle is important for safetly..), and freezing the water, the bottle will split as the water expands on forming ice... which shows you that the same mass of water takes up more space (is less dense) when frozen than as a liquid.
 

Another common demonstration of this phenomenon, well known to scientists and plumbers, is a burst pipe caused when the water in the pipe freezes. The expansion of the ice quite literally rips the pipe apart.
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #32 on: 17/04/2011 20:55:43 »
Quote
Rosy, doesn't water compact as it frezzes? shouldn't the density be highier at 0, as the atoms are more compacted than at density at 4 oC?
No. Water doesn't compact as it freezes, and the maximum density of water occurs at 4 oC. Water's funny stuff. I'm not going to try to explain in any detail here, because it needs diagrams, but there's lots of information on the internet about this. For example this page: http://kentsimmons.uwinnipeg.ca/cm1504/water.htm

On a more hands-on level, consider an ice cube made in your freezer to cool a drink. Not being made from snow, it doesn't contain (a significant number of) bubbles, and yet it floats. If you think about it, I'm pretty sure this is something you know and understand! The density of ice is, inherently, less than that of water at the same temperature. Equally, if you close up a bottle full to the top with water at room temperature (using a plastic bottle is important for safetly..), and freezing the water, the bottle will split as the water expands on forming ice... which shows you that the same mass of water takes up more space (is less dense) when frozen than as a liquid.

Incidentally, if ice didn't float, and if the coldest water didn't float on top of water at 4 oC, then the coldest water would sink to the bottom of lakes and rivers, and they'd freeze from the bottom up. That would mean that instead of a layer of ice over liquid water the whole of the lake would freeze, which would kill the fish and other animals living in the water whereas in reality they can hide in the relatively warm water at the bottom until spring.

Like ice in your drink, it floats. I also saw somewhere that water holds it's temperture, which I suppose is why, water in a bottle placed in the frezzer, frezzes around the outside first then moves inward, strange tho I always saw it as cold compresses and heat expands.

As a stab in the dark could it not be a molecular brake down? what I mean is, does the water gives off atoms as it freezes? Meaining you get pockets of oxegen and hydorgen with-in a compressed H2O ice? Expansion comming from having three things H, O and H2o ice, not just h2o water? The atoms individually take up more space then they do binded as water.

So it does compact but breaks down as it does so becomming slightly smaller as ice, but bigger in overall volume beacuse of trapped gases?

 
« Last Edit: 17/04/2011 22:36:21 by Wiybit »
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #33 on: 17/04/2011 21:45:42 »
Hi Wiybit, sorry that I didn’t have time to respond straight away to the points you raised on 16/04/2011 @ 20:48:50 and today @ 13:40:20. I don’t want to get distracted from the focus of my question about “Another Hockey Stick Illusion?”, i.e. why the “experts” ignore kinetic in favour of collision diameter. If it’s OK with you I’ll leave it to the Naked Scientists to respond to any that I see as a side-issue. You may have to raise such questions separately in order to attract their attention.

Quote
.. Seriuosly you shouldn't encourage them(if you get me) ..
is not the reason that I joined this blog. I will do my utmost to encourage The Naked Scientists to offer their expertise where it relates to my question. I’m very disappointed that I’ve had nothing from them yet and the appropriate laws of molecular dynamics covering the movement of atmospheric gases in firn are certainly relevant.

You didn't get me, I meant encourage them to argue, Ref: your past complaint.


Quote
.. BC can be slightly funny at times, but generally he's ok, when not .. trying to catch you out(so he can laugh at you) ..
is fine for anyone who has come here to be amused but I’m not in that category. I’m here to learn as much as I can about the science relevant to my question. So far the only person on this blog to help improve my understanding is you through your questions.

They(the others that have replied to you) would probably argue that they have tried to help you, but that you have not understood their answers, I will say having some experience of this type of issue, that both side often have a part to play in better communication.

You jumped in quiet early and accused BenV of knowing nothing, he could have just not had time to check in, not to say that others couldn't have responded, but at the same time this is a public family educational forum and there are not so many scientists among the many posters on here, there are many people with a general interest in science but as a percentage I think you'll find the majority of posters on here are interested in science but not actually scientists, I'm not actually sure of the actual numbers of actual scientists on here, not forgetting that most of the scientists on here are specialised in certain fields.
But I am sure they are always looking for more scientists to join, I tried to get a girl studying biotechnology to join the other day.

Also not forgetting the time issues, scientists that do post on here are doing so in their spare time generally. 


Regarding
Quote
.. you still haven't said what it is about Co2 that causes it to act so differently to the other elements, surely HE should move more, in ice if it's smaller and lighter? ..
one day I may be able to fully answer the first part with confidence. All that I can say for the moment is that it is something to do with the bonding between the one C and two O atoms that make up a molecule and the interaction of each molecule with other molecules (N2, O2, Ar, CH4, H2O, etc. Why not put that question to The Naked Scientists.

But it relates to your general question, and is only an issue "if" kinetics of Co2 in ice are true, and as far as I can tell that is still part of your main question and so not answered either. Surely first we find out if the kinetic factors are real then ask why does the Co2 move. I asked you because I believed you understood the kinetic science but didn't understand why they ignored it.


As for the second part, He, being smaller even than CO2, does experience size-dependent fractionation, as described in the paper “Evidence for molecular size dependent gas fractionation in firn air derived from noble gases, oxygen, and nitrogen measurements” by Huber et al (http://icebubbles.ucsd.edu/Publications/Huber_closeoff_EPSL2006.pdf).

It is worthwhile looking more closely at that paper, because as well as answering your question about He directly, it expands on my earlier comment (on 14/04/2011 21:38:13) about Huber, Severinghaus (one of the co-arthors) and that magic 0.36nm molecule diameter
Quote
Abstract .. For smaller gas species (mainly He and Ne) the fractionation factors are linearly correlated to the molecule size, whereas for diameters greater than about 3.6 Å the fractionation seems to be significantly smaller or even negligible ..

Note that Table 2 presents the molecular diameters used in their model and the close-off fractionation factor it produced for 8 of the atmospheric gases, including CO2 and He, but also note that those diameters are collision, not kinetic. Fig. 8 presents a useful graph of 7 of those computer-modelled close-off fractionation factors, with He down at the bottom of the curve, but note which one is missing, dear old CO2. I mentioned in that earlier comment that I had asked Severinghaus why he used collision rather than kinetic diameter and if he had tried his model using CO2’s 0.33nm kinetic diameter instead of its 0.39nm collision diameter. As I said, he chose not to respond directly to those questions. Have a guess where CO2 would have been if he had used kinetic diameter, which I hypothesise is the appropriate measure.

It's never a good sign if a scientist ignores your question relating to their research, it's either an unknown variables or maybe he felt he need time to formulate a responce and so felt it was too much hassle. Under the law apparently the see silence as agreement, so a non reply could be seen as an acknowledgement that the research wasn't so good; But I cannot speak for him. 



That is why I challenge the conclusion that
Quote
.. Close-off fractionation factors for different gases depend strongly on the diameter. The mass of the molecule is less important, since the effect on isotope ratios is very low. The critical size of about 3.6 Å seems to be an upper limit up to which molecules fractionate during the close-off process in the firn. A possible explanation for this could be the diffusion of molecules through channels in the ice lattice. From our findings we believe that the effect of close-off fractionation is nonexistent or at least very small for isotope ratios and for large molecules, like Xe, Kr, N2, CO2, CH4, and N2O. This is an important confirmation for the integrity of polar ice cores as a climate archive of the ancient atmospheric composition of these gases ..

You know if you keep this up you could publish your own findings, you might need some assistance in generating a scientific paper, but why not?

That is how a lot of science moves and works today.



But I’m only a retired Chartered Electrical Engineer and Geezer reasonably says
Quote
.. I find it interesting that anyone who is unaware of why ice cubes float in water might think they are qualified to call into question the scientific credentials of anyone else ..
That is why during the past year I have requested help from “experts” like Severinghaus, Alley, Bender, etc. etc. etc.

Well it is a rather meany thing to say, and surely depending on fields lots of scientists do not understand different areas of science, not understanding certain processes even simple ones like why ice floats hardly makes a person stupid, or incapable to see a bad decision made by a doctor and so seek a second opinion as a simple example.
Could be seen as a elitist statement but Geezer isn't that bad, even if the old stick waving git animaton gives that appearence. I know you pain tho.

It's weird how just comming from different places and ways of thinking about subjects causes terms and there meanings to be interprited differently. What I will say is that it appears you have been asking about this for a while in many different places and become a bit "battle hardened", reactions come from actions and all sides are often guilty of over reacting to some degree at times, just chill, getting upset does nothing to futher investigation and often will draw coversations to a close(and there are some that like to cause conflict to achieve that end).



and now from this “ .. media-savvy group of physicians and researchers from Cambridge University .. ”, but I’m still not getting an answer.

Well Chris is the founder and he is involved in medicine and biology I believe, So I doubt Global warming is his field, I do not know if there are any climatologists actually on here, hence which ever of the scientists answer you, they will all probably be working outside their main fields. It appears you think that all the cambridge scientists are involved with the site but it's a voluntary forum, ergo I think many are not.

I can see what you are looking for, someone that knows their field and can answer the questions you have, this site is connected to Cambridge, so potentially there might be someone that knows someone who get you an answer. 

But understand that tho, it was your assumption that whole of cambridge uni science wing posted on here. Rather, the people that do, are doing so to help out and out of their own free time.

that ofcourse is what I believe, I cannot speak for NS, it's just my interpritation having been on here a while. But you know, they do so to help out even if they cannot answer all your questions atleast they try to.

« Last Edit: 17/04/2011 22:28:15 by Wiybit »
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #34 on: 17/04/2011 22:40:44 »
Actually Pete lets just ask the main crux of your question.

Why Do climatologists ignore the kinetic movement of CO2 in ice, as that could, and probably does effect the ice core Co2 levels?

Anyone?
 

Offline Geezer

  • Neilep Level Member
  • ******
  • Posts: 8328
  • "Vive la résistance!"
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #35 on: 18/04/2011 07:53:17 »
Actually Pete lets just ask the main crux of your question.

Why Do climatologists ignore the kinetic movement of CO2 in ice, as that could, and probably does effect the ice core Co2 levels?

Anyone?

I think that's exactly what Ben said he would followup on.

If Pete was less interested in whizzing all over TNS and those in the "Scientific Community" who are obviously conspiring against him, we could have got there a long time ago without all this infernal palaver. 
 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #36 on: 18/04/2011 10:04:48 »
Hi Wiybit, In your comment of 17/04/2011 @ 21:45:42 you make some fair points that don’t relate directly to my question so I propose to take them over to my other post where I am enquiring into the areas of science where The Naked Scientists are  competent to comment on.
I agree with your comment of  17/04/2011 @ 22:40:44 that we concentrate on the question that I asked here initially.

About my suggestion that you put a question to the Naked Scientists of why CO2 acts in the way that it does you said
Quote
.. But it relates to your general question, and is only an issue "if" kinetics of Co2 in ice are true, and as far as I can tell that is still part of your main question and so not answered either. Surely first we find out if the kinetic factors are real then ask why does the Co2 move. I asked you because I believed you understood the kinetic science but didn't understand why they ignored it ..
I thought that I had made it clear that the “experts” to whom I have put my question are aware of the size-dependent fractionation that occurs (in your terminology “the kinetic factors are real”) but use a different (in my hypothesis an incorrect) measure of the estimated size of molecules when modelling their movement within the porous firn.

Collision Diameter:
Quote
.. (physical chemistry) The distance between the centers of two molecules taking part in a collision at the time of their closest approach
(http://www.answers.com/topic/collision-diameter#ixzz1Jr9mx600). As I understand it this applies to molecules whizzing about in a space that is large compared to their size, i.e. normal diffusion of gases and in my opinion relevant in the upper levels of an ice sheet.

Kinetic Diameter:
Quote
.. The kinetic diameter can be understood as the diameter of a pore needed to let that specific molecule pass ..
(http://www.patentstorm.us/patents/7214719/description.html), in my opinion relevant in the lower levels of an ice sheet as it approaches close-off.

As I have repeated ad-nauseam in my exchanges with the “experts”, kinetic diamter is the measure used by gas purification practitioners in their patented and working purification systems. As the patent above says (albeit in relation to
Quote
.. Separating of water .. in particular with H2, CO, CO2, CH4 and higher alkanes ..
(H2O kinetic diameter 0.27nm) 
Quote
.. separation on size is possible, when the components to be separated are small enough in kinetic diameter to migrate through the zeolite pores and the components from which they have to be separated have a kinetic diameter that is too large ..

If you want to find out more about the difference between the two measures there is an excellent book “Materials science of membranes for gas and vapor separation” (http://books.google.co.uk/books?id=Hc6ioeRc7p8C&pg=PA8&lpg=PA8&dq=H2O+%22collision+diameter%22&source=bl&ots=p1PsILlfsd&sig=sNWlODlE3Y4gmadOscv_BDvoTRg&hl=en&ei=0OarTanCDIeg8QPA-Oy4Ag&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBYQ6AEwAA#v=onepage&q=H2O%20%22collision%20diameter%22&f=false).   Pages 7-10 and Table 3.1 “Properties of Gases” on Page 96 are particularly relevant and will give you an idea of the complexity of the subject. If I can’t extract an answer to this fundamental question from the ice core “experts” I may well be forced into buying that book and finding an expert in molecular dynamics who is prepared to spend the time giving me
Quote
.. some assistance in generating a scientific paper ..

But surely if I have to do that it begs the question “Why haven’t the paleoclimatologists done this already?”. After all, Professor Jaworowski raised this specific fundamental issue of size-dependent fractionation in 1992 and Huber, Severinghaus and their co-authors were researching it at least as long ago as 2004 (http://icebubbles.ucsd.edu/Publications/Huber_closeoff_EPSL2006.pdf).

I agree that
Quote
.. It's never a good sign if a scientist ignores your question relating to their research, it's either an unknown variables ..
but do not think, under the circumstances, that they should
Quote
.. need time to formulate a responce and so felt it was too much hassle

You and Geezer, appear to defend The Naked Scientists because they may not have expertise in climate science. I would not be here if they had not given me the impression of having a section within their "Environment" area specifically on Climate Change and having their representatives advising on it. If I don’t have expertise then I admit it. Surely it is not asking too much for a simple statement on their “About” page making it clear in what areas they are competent to speak?

Geezer I did not come here for the purpose of
Quote
.. whizzing all over TNS and those in the "Scientific Community" who are obviously conspiring ..
As I explained in my opening question
Quote
I came across this blog while searching for detailed pictures of ice extracted from deep down an ice sheet. I have a question that has been puzzling me for over a year now and remains unanswered despite asking it of experts in the subject ..
The Naked Scientists gave me the impression of having access to experts in this subject because when I Googled - “Ice Cores” climate – I was taken to
Quote
Climate Change and Ice Cores. Dr Eric Wolff from the British Antarctic Survey
(see that lovely picture of bubbles in ice) and thought “Hey, at last I might make headway.

I then looked at TNS’s “About” page (http://www.thenakedscientists.com/HTML/about-us/) and thought “Yes, this is promising” because
Quote
The Naked Scientists are a media-savvy group of physicians and researchers from Cambridge University ..
but then I saw the photo and thought “Is this a joke?”. Never mind, I persevered and looked at the
Quote
Who are we?”
page (http://www.thenakedscientists.com/HTML/about-us/who-are-we/) and thought “OK, that ‘photo is just high-spirited youngsters having a laugh. There are three archaeologists, a zoologist, a couple of astronomers, all apparently from Cambridge University, with contacts with specialists who can answer my question.

What was the outcome? Only one of those Naked Scientist, their kitchen science specialist BenV, responds, first simply asking
Quote
So what's your question here Pete?
despite my question having been spelled out clearly in my first paragraph
Quote
.. why do paleo-climatologists use collision diameter in preference to kinetic diameter when considering the migration of air molecules through firn and ice ..

BenV then follows up with
Quote
I don't recall claiming any expertise in migration of molecules through any medium, so it's no surprise you find me lacking in that arena ..

Is there any wonder that I might be getting somewhat irritated. I asked a straight forward question of a group who I understood from their own promotional material and the content of their blog could find an answer for me and provided background information about it to help elicit a worthwhile response and all I get is “what was your question” and “I can’t answer it”. If I have over-reacted then I sincerely apologise, but I think I have pointed out here already, I arrived here after already getting rather irritated by “experts” refusing to respond to my simple question about kinetic v collision diameter.

Please Naked Scientists can you find someone who is knowledgeable enough to provide a straight answer to my fundamental question.

Best regards, Pete Ridley
« Last Edit: 18/04/2011 11:04:07 by Pete Ridley »
 

Offline BenV

  • Neilep Level Member
  • ******
  • Posts: 1503
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #37 on: 18/04/2011 12:34:16 »
As I said, Pete, I will try to put it to someone relevant when I next have an opportunity.

Also, I explained to you why my first comment was about your specific question - because the huge block of text means some people will not read it, discover your question and engage, and I was subsequently proved to be  correct.  Might I also suggest that your rather aggressive posts may lead to some people who may be able to help being disinclined to do so, and would rather not get involved?
« Last Edit: 18/04/2011 12:37:07 by BenV »
 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #38 on: 18/04/2011 12:45:33 »
Hi BenV, thanks for trying to find someone to whom you can put my question. Hopefully it won’t take you long to find someone who understands the subject and is prepared to spend a little time educating me.

Best regards, Pete Ridley
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #39 on: 18/04/2011 16:50:31 »
 
Quote
About my suggestion that you put a question to the Naked Scientists of why CO2 acts in the way that it does you said
Quote
.. But it relates to your general question, and is only an issue "if" kinetics of Co2 in ice are true, and as far as I can tell that is still part of your main question and so not answered either. Surely first we find out if the kinetic factors are real then ask why does the Co2 move. I asked you because I believed you understood the kinetic science but didn't understand why they ignored it ..
I thought that I had made it clear that the “experts” to whom I have put my question are aware of the size-dependent fractionation that occurs (in your terminology “the kinetic factors are real”) but use a different (in my hypothesis an incorrect) measure of the estimated size of molecules when modelling their movement within the porous firn.

So you are therefore saying that you know why Co2 moves as it does, and know of a better way to model it?

Quote
You and Geezer, appear to defend The Naked Scientists because they may not have expertise in climate science. I would not be here if they had not given me the impression of having a to, section within their "Environment" area specifically on Climate Change and having their representatives advising on it. If I don’t have expertise then I admit it. Surely it is not asking too much for a simple statement on their “About” page making it clear in what areas they are competent to speak?

Except enviroment is a huge area of science, I'll defend anyone where I see a need to, I critic also, I just try to be fair that's all. 
 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #40 on: 18/04/2011 18:59:37 »
Hi Wiybit, your
Quote
So you are therefore saying that you know why Co2 moves as it does, and know of a better way to model it?
is way off beam. I have never said that so please don’t distort what I say. You can check my previous comments and the links to other comments of mine elsewhere to refresh your memory on what I am saying.

Regarding
Quote
Except enviroment is a huge area of science ..
I am only really interested in talking about climate change and on this thread only in getting an answer to my question about kinetic v collision diameter from someone having the required level of expertise. I thought that I had made this clear in my very first comment here 5 days ago. Here again is what I said
Quote
.. I have a question that has been puzzling me for over a year now and remains unanswered despite asking it of experts in the subject. My question in a nut shell to the scientists here is “why do paleo-climatologists use collision diameter in preference to kinetic diameter when considering the migration of air molecules through firn and ice”?

I can’t see anything ambiguous about that excepting perhaps for someone who doesn't know what firn is or why paleo-climatologists are interested in the movement of air molecules in ice. I don’t recall having commented here on any other aspect of the environment.

Hopefully BenV will soon be able to find someone who has the necessary expertise and inclination to give me a satisfactory answer

Best regards, Pete Ridley
« Last Edit: 18/04/2011 19:53:55 by Pete Ridley »
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #41 on: 18/04/2011 19:57:37 »
Hi Wiybit, your
Quote
So you are therefore saying that you know why Co2 moves as it does, and know of a better way to model it?
is way off beam. I have never said that so please don’t distort what I say. You can check my previous comments and the links to other comments of mine elsewhere to refresh your memory on what I am saying.

That's fine I never intended to distort what you said, I asked a question, knowing that we had discussed that before(generally you say NS people can answer you) you stated that under your hypothesis, that the way they currently model is inncorrect, and the way you believe they should model, would work better.

There is the problem you suggest an understanding of the models and propose what you consider to be a better way, yet you are talking in open Hypothicals. That lead me ask what I did because you failed to clarify your understanding.

I am kinda left to conclude that you have a basic understanding of how they do the maths, you see there are things they ignore and are certain they are wrong, yet at times express yourself with a certainity that you really do not have.

Does that make sense? I am not saying that to have a go at you, I have been trying to help you find an answer to your question and still am, but to express certainity when you are not, is slightly contradictory.


Regarding
Quote
Except enviroment is a huge area of science ..
I am only really interested in talking about climate change and on this thread

Maybe but that does not chage the reality that enviromental issues and topics are far farer reaching than just climate change, just because there is a enviromental section does not mean you should expect every type of enviromental scientist to be present.

 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #42 on: 18/04/2011 21:27:37 »
Hi Wiybit, In my second comment here, on 13/04/2011 @ 21:58:19, I said specifically for your benefit [quote .. The researchers that I mentioned in my first comment ignore kinetic diameter and use collision diameter, which I hypothesise is not appropriate when the diameter of pores within and the channels that link ice air pockets approach the size of those smaller molecules as the ice is reaching the final stages of compression to a state where the air pockets become “closed off”[/quote] Note that phrase “ .. which I hypothesise .. ”.
My definition of hypothesise is pretty close to the following
Quote
Verb   1.   hypothesise  - to believe especially on uncertain or tentative grounds;
(http://www.thefreedictionary.com/hypothesise).

If you use a different definition then that could account for why you incorrectly say
Quote
.. So you are therefore saying that you know why Co2 moves as it does, and know of a better way to model it?
Hypothesising (i.e. speculating) is a long way off knowing therefore your statement was, as I said before
Quote
.. way off beam ..

I don’t believe that my hypothesis says that
Quote
.. the way they currently model is inncorrect, and the way .. they should model, would work better
It only says that I speculate that they should use a different measure of molecular diameter in their models.

You say
Quote
.. There is the problem you suggest an understanding of the models and propose what you consider to be a better way ..
but I don’t think that I have ever claimed to know any details of how their models work. All that I know is that they say they use collision diameter in their modelling and I speculate that they should be using kinetic diameter (and asked Severinghaus if he had run his model using that measure).

It is because I speculate about this that I have repeatedly asked the “experts” to explain why they choose to use collision diameter. In my opinion that is simply proposing the use of a different parameter, not proposing a better way of modelling the process. I’m not qualified to do the latter, but am entitled to speculate about using an alternative measure that I understand is used by gas purification practitioners in their operational systems when considering similar processes. The use of this alternative measure could well overturn the conclusions that the ice core “experts” draw from the results of their modelling about their ability to reconstruct past atmospheric concentration of CO2.

I think that I have provided you with an excellent reference book (“Materials science of membranes for gas and vapor separation”) from which, if you are inclined, you can develop a better understanding of the circumstances under which the different measures of molecular diameter are applied.

I don’t understand how you can conclude that I
Quote
.. have a basic understanding of how they do the maths, .. see there are things they ignore and are certain they are wrong ..
. I have questioned only one thing, why do they prefer collision over kinetic diameter. If I was “certain they are wrong” I would say loud and clear “you are using the wrong measure of molecular size”. Have I done that? If you think so then please tell me where I said it and I’ll withdraw the comment.

As for your
Quote
.. enviromental issues and topics are far farer reaching than just climate change, just because there is a enviromental section does not mean you should expect every type of enviromental scientist to be present ..
have you looked at the categories that The Naked Scientists list under the Life Sciences forum heading “The Environment”? They are
Quote
.. Meteorology, ecology, climate change and conservation
(http://www.thenakedscientists.com/forum/).

Best regards, Pete Ridley
« Last Edit: 18/04/2011 21:31:19 by Pete Ridley »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11978
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #43 on: 19/04/2011 04:02:33 »
Wow, this thread should really attract interest :)

It has all the ingredients. A lot of 'learned words' and it's argumentative in the best/worst American definition of a so called high school 'debate'. Furthermore it sounds as if it knows what it discuss :) also effectively telling those that don't agree that they are ignorants :)

I do not expect Ben to be such a person Peter. I expect him to know his limits exquisitely well, and what's even better, acknowledging them too :) which is more than I can say about some. The road to wisdom is to know when you're out of your depth, which won't stop us from making educated guesses though :) You come to the site, telling moderators that they 'don't know what they are talking about', thereby implicating that you do :) (by inference there). A classical debate trick, often used in those society's thriving on 'free debate', throwing verbal manure at each other.

Why not try to see if you can shorten your question instead? To something more simple and understandable. That's what Einstein did, and if he could so can you, right?

But as I read you it's a question of if we can prove that the ice samples containing air bubbles can be guaranteed to have the exact same atmosphere (and CO2 concentration?) As there was in the atmosphere when the ice layers came to be historically? I might be wrong as I lost myself in your formulations repeatedly, but if that was what you meant, I think the question is valid, and good.

"Such air is found in bubbles trapped in annual layers of ice in Antarctica, in sealed brass buttons on old uniforms, airtight bottles of wine of known vintage, etc. Additional support comes from well-dated carbon-isotope signatures, for example, in annual tree rings. Estimates of "pre-industrial" CO2 can also be obtained by first calculating the ratio of the recent atmospheric CO2 increases to recent fossil-fuel use, and using past records of fossil-fuel use to extrapolate past atmospheric CO2 concentrations on an annual basis.

Estimates of "pre-industrial" CO2 concentrations obtained in this way are higher than those obtained by more direct measurements; this is believed to be because the effects of widespread land clearing are not accounted for. Ice-core data provide records of earlier concentrations. For concentrations back to about 1775, see A. Neftel et al.

The record derived from the DSS Antarctic ice core indicates an average concentration of 280.05 ppm from 1000-1750 C.E. For over 400,000 years of ice-core record from Vostok, see J. M. Barnola et al.. For ice-core records extending over 650,000 years back in time, see Siegenthaler et al. (2005)." From Recent Greenhouse Gas Concentrations
==

"The latest results from the EPICA core in Antarctica have just been published this week in Science (Siegenthaler et al. and Spahni et al.). This ice core extended the record of Antarctic climate back to maybe 800,000 years, and the first 650,000 years of ice have now been analysed for greenhouse gas concentrations saved in tiny bubbles. The records for CO2, CH4 and N2O both confirm the Vostok records that have been available for a few years now, and extend them over another 4 glacial-interglacial cycles. This is a landmark result and a strong testament to the almost heroic efforts in the field to bring back these samples from over 3km deep in the Antarctica ice. So what do these new data tell us, and where might they lead?

Composite CO2: Click to enlargeFirst of all, the results demonstrate clearly that the relationship between climate and CO2 that had been deduced from the Vostok core appears remarkably robust. This is despite a significant change in the patterns of glacial-interglacial changes prior to 400,000 years ago. The ‘EPICA challenge’ was laid down a few months ago for people working on carbon cycle models to predict whether this would be the case, and mostly the predictions were right on the mark. (Who says climate predictions can’t be verified?).

It should also go almost without saying that lingering doubts about the reproducibility of the ice core gas records should now be completely dispelled.

That a number of different labs, looking at ice from different locations, extracted with different methods all give very similar answers, is a powerful indication that what they are measuring is real. Where there are problems (for instance in N2O in very dusty ice), those problems are clearly found and that data discarded.

Secondly, these results will allow paleoclimatologists to really look in detail at the differences between the different interglacials in the past. The previous 3 before our current era look quite similar to each other and were quite short (around 10,000 years). The one 400,000 years ago (Marine Isotope Stage 11, for those who count that way) was hypotheisied to look more like the Holocene and appears to be significantly longer (around 30,000 years).

Many of the details though weren’t completely clear in the Vostok data, but should now be much better resolved. This may help address some of the ideas put forward by Ruddiman (2003, 2005), and also help assess how long our current warm period is likely to last.

More generally, since the extra interglacials that are now resolved have very different characteristics from the previous ones, they may allow us to test climate theories and models over a whole new suite of test cases. To quote Richard Alley “Whether you’re a physicist, a chemist, a biologist, a geologist, or any other “ist” studying the Earth system, there is something in these data that confirms much of your understanding of the planet and then challenges some piece of your understanding”. It’s all very exciting (for us ‘ists’ at least!)." From 2005. RealClimate.

And this one might give some insight too. Reliability of ice-core science: historical insights. As well as this. Atmospheric nitrous oxide during the last 140000 years (.pdf) That takes up the nitrous oxide question mentioned in RealClimate.

( But the only way to really prove that this isn't another of those mad potconjunctures cooked up by those conspiratorial climatologists, physicists and geologists (et al:) is naturally to do as Methuselah. If we just could find someone like him. Even though he is said to only have lived a measly 1000 y it would still be of interest I think? Providing that he regularly corked those air samples, or Jonah maybe, naah, not him? The flying Dutchman then? And hey, i got it. That roman soldier that was there at the crucifixion, doomed to live forever, then we could, at last, get some good ol'human, down to earth, correlations to test it against :)

As it is we have to make do with what we have, and correlate it to other sources and see if the concentrations agree, and when not, try to find the reasons for the discrepancy.
==

Lastly.

"The most direct method of investigating past variations of the atmospheric CO2 concentration before 1958, when continuous direct atmospheric CO2 measurements started, is the analysis of air extracted from suitable ice cores. Here we present a new detailed CO2 record from the Dronning Maud Land (DML) ice core, drilled in the framework of the European Project for Ice Coring in Antarctica (EPICA) and some new measurements on a previously drilled ice core from the South Pole. The DML CO2 record shows an increase from about 278 to 282 parts per million by volume (ppmv) between ad 1000 and ad 1200 and a fairly continuous decrease to a mean value of about 277 ppmv around ad 1700. While the new South Pole measurements agree well with DML at the minimum at ad 1700 they are on average about 2 ppmv lower during the period ad 1000–1500. Published measurements from the coastal high-accumulation site Law Dome are considered as very reliable because of the reproducibility of the measurements, high temporal resolution and an accurate time scale.

Other Antarctic ice cores could not, or only partly, reproduce the pre-industrial measurements from Law Dome. A comparison of the trends of DML and Law Dome shows a general agreement. However we should be able to rule out co-variations caused by the same artefact. Two possible effects are discussed, first production of CO2 by chemical reactions and second diffusion of dissolved air through the ice matrix into the bubbles. While the first effect cannot be totally excluded, comparison of the Law Dome and DML record shows that dissolved air diffusing to bubbles cannot be responsible for the pre-industrial variation. Therefore, the new record is not a proof of the Law Dome results but the first very strong support from an ice core of the Antarctic plateau."

By SIEGENTHALER, U., MONNIN, E., KAWAMURA, K., SPAHNI, R., SCHWANDER, J., STAUFFER, B., STOCKER, T. F., BARNOLA, J.-M. and FISCHER, H. (2005), from 1. Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland 2. CNRS Laboratoire de Glaciologie et de Géophysique de l'Environnement (LGGE), Grenoble, France 3. Alfred Wegener Institut für Polar- und Meeresforschung, Bremerhaven, Germany.

But as that one is 'pay for view' from Wiley Online Library / Wiley InterScience I can't link that pdf, which is a shame. Anyway, you got some references I hope. If that now was your question?
==

As for kinetic diameter, versus collision diameter? Well, exactly how should we construct that experiment? over what time period? We have the ice cores from 'human reckoning' to compare to trees, rocks, sediment etc of course. And they do seem to fit/correlate to each other? Although that only should be over a measly ?? Thousand years maybe, or so :) Could that make do for a comparison/verification?
« Last Edit: 19/04/2011 04:24:02 by yor_on »
 

Offline Pete Ridley

  • Full Member
  • ***
  • Posts: 60
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #44 on: 19/04/2011 12:45:36 »
Hi yor_on, I had wondered if it would be long before you turned up here. I have seen comments of yours relating to questions about both “climate change” and “Physics, Astronomy & Cosmology” topics and the impression that I get is that you have a good understanding of the latter. I expect that you would even be able to make a worthwhile contribution to the work that Professor Andrew White is doing at CERN (my comment on 17th @ 11:36:14).

It seems to me that you express opinions on the former from a position of ignorance comparable to mine, so may have more to learn from the exchanges here than to contribute. Of course I may be wrong so, even though you use a false name, are you prepared to disclose the extent of your scientific expertise in the subject of molecular dynamics beyond that you may be a good runner (http://www.thenakedscientists.com/forum/index.php?action=profile;u=9199)?

Your 1612-word comment quotes from and links to some very interesting stuff about those attempts to reconstruct past atmospheric CO2 content using air “trapped” in ice for decades, centuries and millennia (although I am always suspicious of anything that appears in that “Hockey Team” blog Realclimate) but it does nothing that answers my simple question.

You ask
Quote
Why not try to see if you can shorten your question instead?
but how much shorter than
Quote
.. why do paleo-climatologists use collision diameter in preference to kinetic diameter when considering the migration of air molecules through firn and ice ..
do you need? I stated that simple question in my opening comment on The Naked Scientists blog and have repeated it twice on this very page, only yesterday at 10:04:48 then again at 18:59:37. Have you bothered to read this thread before commenting or have you simply jumped in blind? How you can paraphrase that simple question as
Quote
it's a question of if we can prove that the ice samples containing air bubbles can be guaranteed to have the exact same atmosphere (and CO2 concentration?) As there was in the atmosphere when the ice layers came to be historically?
is beyond me.

So, your
Quote
Anyway, you got some references I hope. If that now was your question?
is way off beam because you have simply provided quotations and links that contributed to answering your own mistaken interpretation of my question.

Your
Quote
As for kinetic diameter, versus collision diameter? Well, exactly how should we construct that experiment? over what time period?
again has nothing to do with my simple question. As far as I am aware I have not asked for any experiment about kinetic v collision diameter so please would you point to where you think that I have done so. What I have done is ask Professor Jeff Severinghaus, one of the “experts”, if they have run their model substituting kinetic for collision diameter.

I have already had discussions with Professors Richard Alley, Severinghaus and Bender about the other proxies such as
Quote
.. trees, rocks, sediment etc of course ..
and my scepticism about the statistical manipulations used to make them
Quote
..  fit/correlate to each other

You may find the article “Uncertainty in Climate Change (WP)” by A.T. Grove and E. Lopez-Gunn (http://www.realinstitutoelcano.org/wps/portal/rielcano_eng/Content?WCM_GLOBAL_CONTEXT=/elcano/elcano_in/zonas_in/dt25-2010) of interest but that really is another question which I suggest that you raise separately if you wish to learn something about those other proxies.

Best regards, Pete Ridley

 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11978
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #45 on: 19/04/2011 12:56:45 »
Peter I'm always in a state of confusion :)

It's only when I've finally translated what others say and tell me into my own that I understand what they mean. That's also why I wondered what you meant, you see on TNS we have all kind of expertise, but only a very few of them, if any, believe themselves to be modern Leonardo Da Vinci's. Insulting remarks usually lead to a ban here. We're not really interested in mudslinging,  we are interested in learning and sharing what we know though. It can become a difficult balance act to know where one end (learning) and the other takes over (mudslinging) but we try :)

As for your reference I will look at it, but to build the contention on your idea of the difference, without presenting anyone agreeing is a hard thing to do. Doesn't necessarily mean that your ideas is wrong but you should really try to find some supporting evidence before contending what everyone 'mainstream' think is true. And that's why I asked you for ideas of how you would like to see a experiment made.

You seem quite skilled in innuendo and debate technique though :)
==

As for the 'think tank' you linked me too? Driven by business, for business maybe, with the trustees and corporations being made board members, maybe? See, I can do innuendo too :)

It's been in my sorry experience that when I read about some new, or not so new, 'institution' contending climate science, I always will benefit from looking at its 'founders'. All to often you can find that, although all of those organizations proudly declaring themselves 'independent', that they in deed are influenced by the ideas of their 'financial support'. Which in a way is nothing remarkable, just a human fact. It's very hard to make anything 'independently' outside the academic sphere, if even there(?) nowadays. Not even 'independent investigating journalism' is really independent today, as can be seen in any modern war, and how those journalist finds the opportunity to report 'independent views'?

But yes, I will read it. I always do.
« Last Edit: 19/04/2011 13:22:46 by yor_on »
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11978
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #46 on: 19/04/2011 14:32:42 »
Well I looked it over. Actually a quite nice article, summarizing what we think us know, staying somewhat on the conservative side, carefully avoiding to discuss man made contributions more than in passing. It's a good one I think, I will have to reread it later. As for now I'm still not fully awake. Take me a lot of coffee to get me working those days :)

And I'm not really making fun of you, even though I found the discussion quite inflamed. I'm interested in how you think you could prove your point, and to me that would need 'experimenting'. Assume that we had climatologists here that research, I doubt that they would get involved in this myself. But if you could present a way to simply test it, and that should mean a long term test of it also as I see it, realistically. Maybe some of them would get ideas from a proposition?

So, if it was you wanting to test it, how would you do it?

Myself I would prefer a 'secluded area', meaning not easily contaminated by human activity, where you could measure the atmospheric conditions continually and then compare the layers of snow/ice to those results you get. That wouldn't exactly answer your 'physics' question, but it would tell us if there was a correlation between the atmosphere and the bubbles formed, and also the isotopes, with what we then would measure continuously.

And that would be the important thing to me. And as I'm guessing this is what your question really discuss too? That is, if we are responsible for the climate changes we observe today, and casting into doubt the foundations on where our climatology builds historically. In this case the ice cores we use for comparison. The real problem with your question is that this is already done, continuously as I see it. And if that ice trapped air would give us the wrong results we should have noticed it by now?

Well, as I see it.
 

Offline yor_on

  • Naked Science Forum GOD!
  • *******
  • Posts: 11978
  • Thanked: 4 times
  • (Ah, yes:) *a table is always good to hide under*
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #47 on: 19/04/2011 17:05:10 »
Here you have a description of some techniques used for differing the time-lines involved and how the measuring is done.

Ice-core evidence of abrupt climate changes. 

And here is some other indirect evidence for it working.

"We reconstructed the radiocarbon activity of intermediate waters in the eastern North Pacific over the past 38,000 years. Radiocarbon activity paralleled that of the atmosphere, except during deglaciation, when intermediate-water values fell by more than 300 per mil. Such a large decrease requires a deglacial injection of very old waters from a deep-ocean carbon reservoir that was previously well isolated from the atmosphere. The timing of intermediate-water radiocarbon depletion closely matches that of atmospheric carbon dioxide rise and effectively traces the redistribution of carbon from the deep ocean to the atmosphere during deglaciation."  From Marine Radiocarbon Evidence for the Mechanism of Deglacial Atmospheric CO2 Rise. (pay site)

And here you have a geological study studying Firn and 'gas transportation' " This study aims to establish the continuity of the gas record at Mt. Moulton, correlate the MBI#1 record to the Vostok EGT4 timescale through the development of MBI#1 age models, interpret the length of the Eemian period in the MBI#1 record and investigate the link between northern hemisphere insolation and Antarctic temperature as expressed in the MBI#1 isotopic temperature record." It also discuss "gas transport within firn" separating it roughly into convection, diffusion and 'non-diffusion', quite interesting in fact. Thesis.

As for the pure physics of it?
'Geology, Palaeontology & Archaeology' ?
Maybe ask in Chemistry?
Or General Science.

It a field where everything goes into everything else it seems.



 
« Last Edit: 19/04/2011 17:10:14 by yor_on »
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #48 on: 19/04/2011 18:16:19 »
I don’t understand how you can conclude that I
Quote
.. have a basic understanding of how they do the maths, .. see there are things they ignore and are certain they are wrong ..
. I have questioned only one thing, why do they prefer collision over kinetic diameter. If I was “certain they are wrong” I would say loud and clear “you are using the wrong measure of molecular size”. Have I done that? If you think so then please tell me where I said it and I’ll withdraw the comment.

No need to withdraw comments, and I am not going to go back through all the past conversations, but I am sure you expressed a certainy before about the methods they used being wrong. My point relating to hypothesis was simply that they can be at varying degrees also, from a hypothesis you are more sure of as a possible explaination to ones more you are less sure of as a possible explaination, by saying "open hypothesis" I meant in the middle.

 


As for your
Quote
.. enviromental issues and topics are far farer reaching than just climate change, just because there is a enviromental section does not mean you should expect every type of enviromental scientist to be present ..
have you looked at the categories that The Naked Scientists list under the Life Sciences forum heading “The Environment”? They are
Quote
.. Meteorology, ecology, climate change and conservation

That still doesn't really change my point.

Besides I was only trying to help you get an answer and I hope that I have, there is no need for us to go on and on about this as you say 'but it says Climate change' and I say but climate change has different areas also...

Peace
 

Offline Jolly- Joliver

  • Hero Member
  • *****
  • Posts: 584
    • View Profile
"Another Hockey Stick Illusion"?
« Reply #49 on: 19/04/2011 18:19:16 »
Assume that we had climatologists here that research, I doubt that they would get involved in this myself. But if you could present a way to simply test it, and that should mean a long term test of it also as I see it, realistically. Maybe some of them would get ideas from a proposition?

So, if it was you wanting to test it, how would you do it?


Rather than going off to the north or south polls could you not use a snow machine? The flakes might be formed slightly differently than in nature but using extraplation it could be a simply way to test it, no? 

All snow flakes are different anyway...
 

The Naked Scientists Forum

"Another Hockey Stick Illusion"?
« Reply #49 on: 19/04/2011 18:19:16 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums
 
Login
Login with username, password and session length